Change calculating coin-return system

ABSTRACT

A fluid-dispensing unit is operable to dispense fluid up to or less than a presettable amount and includes a coin-storage for storing coins of various denominations. A plurality of coin payout mechanisms are provided for paying out coins of the different denominations from the coin storage when a dispensing operation terminates before a preset amount of fluid has been dispensed. Means rotatably drive a plurality of registering cams while fluid is being dispensed from the unit. At the end of a dispensing operation the registering cams assume a stationary angular position which provides an analog indication of change to be returned. Stationary switches operated by the registering cams provide an ON/OFF or digital indication of change to be returned. Means are provided for energizing the coin payout mechanism in accordance with the digital indication provided by the stationary switches, operated by the registering cams.

United States Patent [191 Young Oct. 30, 1973 CHANGE CALCULATING COIN-RETURN SYSTEM [75] Inventor: Robert B. Young, Buena Park, Calif.

[73] Assignee: Pan Nova, Inc., Santa Fe Springs, Calif.

[22] Filed: Dec. 6, 1971 [21] Appl. No.: 204,833

[52] US. Cl 194/13, 222/2, 133/2, 221/9 51 Int. Cl. G07f 13/02 [58] Field of Search 194/13, 10, DIG. 14; 221/9; 133/2, 4; 222/2 [56] References Cited UNITED STATES PATENTS 3,605,973 9/1971 Burke et a1. 194/13 3,080,035 3/1963 Diaz 133/4 R Primary ExaminerSamuel F. Coleman Assistant Examiner-H. Grant Skaggs, Jr. Attorney-Warren L. Kern et a1.

[5 7] ABSTRACT A fluid-dispensing unit is operable to dispense fluid up to or less than a presettable amount and includes a coin-storage for storing coins of various denominations. A plurality of coin payout mechanisms are provided for paying out coins of the different denominations from the coin storage when a dispensing operation terminates before a preset amount of fluid has been dispensed. Means rotatably drive a plurality of registering cams while fluid is being dispensed from the unit. At the end of a dispensing operation the registering cams assume a stationary angular position which provides an analog indication of change to be returned. Stationary switches operated by the registering cams provide an ON/OFF or digital indication of change to be returned. Means are provided for energizing the coin payout mechanism in accordance with the digital indication provided by the stationary switches, operated by the registering cams.

8 Claims, 8 Drawing Figures PATENIEDucI 30 m SHEET 1 [IF 4 PAIENIEnncmo ms 3.768.617 SHEET h 0F 4 Fig. 6

CHANGE CALCULATING COIN-RETURN SYSTEM BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to coin-return systems.

2. Description of the Prior Art Coin-return systems have long been used in various types of coin or token operated machines. In some cases the amount of change to be returned to the customer is variable in that it depends upon how much use is made of the machine. For example, prior art coinoperated, self-service gasoline dispensing units have included coin-return systems which return variable amounts of change. .If the customer fully dispenses a prepaid amount of gasoline from the unit its coin return system does not payout any changeto him. If the customer has dispensed less than the prepaid amount when his gasoline tank fills, the coin return system pays as change the difference between the prepaid amount and the value of the gasoline actually dispensed.

Some prior art systems involve complex mechanical arrangements which are expensive to produce and difficult to maintain. For example, U.S. Pat. No. 3,478,854 discloses a system having a coin-return controller comprising a plurality of cams, the angular position of which represents the change to be returned. A complex mechanical arrangement of pivotally movable arms are provided for sensing the angular positions of the cams and responsive thereto for opening gates to allow coins to be returned.

Other prior art systems take advantage of the relative simplicity and economy of electrically actuated coinreturn mechanisms. In these other prior art systems, the change is paid out from a coin storage by a plurality of electrically actuated payout mechanisms, each of which pays out a single denomination such as a penny, nickel, etc. A limiting factor on the speed with which change can be returned resides in the minimum time in which a payout mechanism can be recycled. For example, when four pennies are due the customer the penny payout mechanism is actuated four times in succession and a certain amount of time must be allowed between actuations An addition limiting factor on the speed with which change can be returned exists in one prior art system having electrically actuated payout mechanisms. This additional limiting factor resides in the serial manner in which the payout mechanisms are actuated. That is, only one of the payout mechanisms is actuated at a time. For example, first, the penny pay mechanism may be actuated a sufficient number of times and then the nickel pay mechanism and so forth. Thus the customers change trickles out coin-by-coin over a relatively long period of time.

In this prior art system, a gasoline dispensing unit has a shaft which rotates while gasoline is being dispensed. When the gasoline tank fills, this shaft stops rotating. A plurality of cams are rotatably coupled to this shaft. The cams have teeth projecting radially outwardly from their periphery similar to a gear. Adjacent to the periphery of each cam is a single microswitch associated with that cam. When change is to be returned a separate motor rotatably drives the cams. As the cams rotate a series of teeth on each cam successively actuate (i.e., close and then open) the single microswitch associated with that cam. Means responsive to the successive closings of the microswitches actuate the payout mechanisms in the above-described serial manner.

SUMMARY OF THE INVENTION This invention is directed to a change calculating coin-return system which returns change more rapidly than prior art systems by returning coins of different denominations substantially simultaneously.

Briefly, the invention includes a coin storage for storing coins of various denominations such as pennies, nickels, etc. A different coin payout mechanism is provided for each different denomination and each mechanism is individually energizable to pay out a coin of its associated denomination. A preset number is stored in a registering means such as a stepping switch. The preset number can correspond to the number of $1.00 credits paid for in advance by a customer. A shaft is provided together with means for rotating it and stopping it before the shaft has rotated through a number of angular degrees which number is proportional to the preset number. Cam means are rotatably coupled to the shaft and are held stationary while the shaft is stopped. While stationary, the cam means provide an analog indication of change to be returned. A plurality of switches operated by the cam means provide an ON/OFF or digital indication corresponding to the analog indication. In contrast to prior art approaches the switches are responsive to the static position of the cam means and operate simultaneously to provide a parallel rather than a serial indication of change due. Means are provided to energize the coin payout mechanisms in response to the digital indication provided by the switches.

Preferably, this invention is embodied in a fluiddispensing unit which is involved in sales transactions usually in excess of a dollar bill. Thus the coin-return system is preferably adapted to return change down to a penny and beyond a dollar. The dispensing unit includes registering means such as a stepping switch and means for controlling the registering means so that it indicates whether and how many dollars are due as change. Means are provided for paying out a pair of half-dollars as change for each dollar indicatedas due by the registering means. The dispensing unit includes a fluid-flow meter and a computer unit having a shaft which rotates while fluid flows through the meter and in proportion to the value of fluid dispensed. The cam means are rotatably coupled to the computer shaft. Preferably, the cam means include a plurality of cams which provide an analog indication of small change (i.e., under $1.00) respectively in small denominations (pennies), intermediate denominations (nickels and dimes), and large denominations (quarters and halfdollars). A plurality of switches are disposed around the periphery of each cam and provide at the same time an indication of how many coins of each denomination are due as change.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 3 is an elevation view of an evaluator assembly comprising a series of cams contained in the dispensing unit of FIG. 1;

FIGS. 4 through 7 illustrate the shape of the cams and the relative angular position of switches operated by the cams in the evaluator assembly; and

FIG. 8 illustrates a motor and camming arrangement for operating other switches involved in the payout operation of the present invention.

DETAILED DESCRIPTION dollar credit. A customer can dispense gasoline from the unit 10 until the value of the gasoline dispensed is equal to the number of credit signals registered for that customer. Alternatively, if the customers gasoline tank fills before he has received his prepaid amount of gasoline he is automatically given change.

The unit 10 includes a conventional gasoline dispenser indicated generally at 20. The dispenser 20 illustrated in FlG. 1 is sold by the Products Services Division of the A. O. Smith Company under the designation Model L-501. The dispenser 20 is housed by top cabinet 21, a supporting frame 22 and cover panels which have been deleted from FIG. 1 to show interior parts.

An inlet pipe 23 carries gasoline pumped to the dispenser 20 by conventional electrically controlled gasoline pump 24 which is electrically connected to the dispenser 20 by a cord 25. A valve assembly indicated generally at 26 is specially added to the aboveidentified Model L-50l and connects the inlet pipe 23 to a strainer assembly 27. The valve assembly 26 includes a solenoid-operated fast flow valve (FFV) and a solenoid-operated slow flow valve (SFV) which control the flow of gasoline between the inlet pipe 23 and the strainer assembly 27. When both the FFV and SFV valves are closed, no gasoline can flow up to the strainer assembly 27. When both the FFV and SFV valves are open, gasoline can flow to the strainer assembly 27 at approximately 40 times the rate at which it can flow when the FFV valve is closed and the SFV valve is open.

When gasoline is being dispensed with both the FFV valve and the SFV valve open, gasoline flows up from the inlet pipe 23 into conventional T-connector 28. A major portion of the gasoline flows upwardly to the strainer assembly 27 through the T-connector 28, the FFV valve, and another T-connector 30. A smaller portion of the gasoline flows outwardly from the T- connector 28 to the SFV valve through tubing 29, from the SFV valve inwardly into the T-connector 30, and upwardly to the strainer assembly 27.

A flow meter 31 is connected to the strainer assembly 27 by a tube 32. A control valve 33 associated with flow meter 31 controls the flow of gasoline through the flow meter 31 and is connected by tube 34 up to a hose coupling 35 mounted on the side of the top cabinet 21.

A hand operated nozzle 36 is connected to the hose coupling 35 through a hose 37. FIG. 1 shows the nozzle in a stored position wherein it is supported by a hook 38.

The flow meter 31 has extending vertically therefrom an output shaft 39 which rotates in proportion to the amount of gasoline dispensed. A computer unit 40 is responsive to the rotation of the output shaft 39 to compute the monetary value of the gasoline dispensed. A computer display unit 41 provides a visual indication of this computed monetary value, the per gallon sales price, and the number of gallons dispensed on a given sale.

A reset lever 42 is secured to a shaft 43 extending horizontally from the computer display unit 41 through a hole of the top cabinet. Before any gasoline is dispensed in any given sales operation, the reset lever 42 is manually rotated so as to reset the computer display unit. A control handle 44 is secured to a shaft 45 also extending horizontally from the computer display unit 42 through a hole in the top cabinet. The control valve 33 associated with the flow meter 31 is opened by a vertically extending linkage 46 operated by the c0mputer display unit 41 in response to rotation of the shaft 45.

A switch box 47 in the top cabinet 21 houses a conventional microswitch, designated in the schematic of FIG. 2 as PCS and which is closed in response to rotation of the control handle 44.

A head box 55 is mounted ori top of the dispenser 20. A tray 56 projects outwardly from the bottom of the head box 55 for catching coins returned from a coin storage by conventional coin return mechanisms contained'therein. A display light 57 is mounted in the head box 55. In the example described, display light 57 is a single digit numerical display light which is sold by the Allard Company. The display light 57 has seven elements arranged in the shape of the number eight, and any one of the 10 decimal digits can be displayed by illuminating appropriate groups of these seven elements. As examples, the number zero is displayed when the six peripheral elements are illuminated and the number eight is displayed when all seven elements are illuminated.

A special box 50 is added to the Model L-501 in the top cabinet 21. FIG. 3 shows an evaluator assembly 200 which is housed by the box 50. FIGS. 4 through 7 show the shapes of various cams which are a part of the evaluator assembly. The evaluator assembly serves a number of functions including the registration of the amount of any small change (i.e., under $1.00) due a customer. The evaluator assembly 200 includes a differential gearing arrangement indicated generally at 201 which has an input shaft 51 and an output shaft 202. The input shaft 51 is connected to a rotatable shaft, (not shown) provided as a standard feature in the computer display unit. In the example described, shaft 51 rotates one complete revolution for each 10 cents worth of gasoline dispensed. An evaluator penny cam (EPC) and an evaluator nickel and dime cam (ENDC) are mounted on the shaft 202. Owing to the gear ratio of the differential gear 201 the EPC and the ENDC cams each rotate one revolution for each 25 cents worth of gasoline dispensed. A zero position cam (ZPC) and an evaluator quarter and half cam (EQHC) are mounted on a shaft 203. A gear arrangement 204 connects the shaft 203 to the shaft 202. Owing to the gear ratio of the gearing arrangement 204 the ZPC and the EQHC cams each rotate one revolution for each one dollars worth of gasoline dispensed. A separate input shaft 205 for the evaluator assembly is connected by a bevel gear drive to a rotatable shaft 48 (FIG. 1). The shaft 48 extends downwardly from an evaluator zeroing motor (EZM) contained in the head box 55 and illustrated in the schematic of FIG. 3.

As indicated in FIG. 4, the ZPC cam has three angular reference positions called the zero position, the subtract position, and the slow flow position, respectively. A microswitch ZPS operated by the ZPC cam is open when the ZPC cam is at the zero position, closes when the ZPC cam rotates to the subtract position, and opens again when the ZPC cam rotates back to the zero position. In the example described the switch ZPS is open for approximately of rotation which corresponds roughly 3 cents worth of gasoline. A microswitch SFS, also operated by the ZPC cam, is open when the ZPC cam is at the zero position, closes when the ZPC cam rotates to the slow flow position, and opens again when the ZPC cam rotates back to the zero position.

As indicated in FIG. 5, the EQHC cam has six angular reference positions and operates three microswitches E75, E50, E25 which are disposed about its periphery. Each of the three microswitches E75, E50, and E25 is open when the evaluator is nulled (i.e., when the ZPC cam is at the zeroposition).

As the EQHC cam rotates, it reaches a 75 cents ON position after about 3.6 of rotation from the null. The

null brings EQHC cam to the cents ON position wherein the E50 switch closes and the E75 switch remains closed. A rotation of 90 from the null brings the EQHC cam to a 75 cents OFF position wherein the E7 5 switch opens and the E50 switch remains closed. A rotation of 179 from the null brings the EQHC cam to the 25 cents ON position wherein the E25 switch closes and the E50 switch remains closed. A rotation of 180 from the null brings the EQHC cam to a 25 cents OFF position. Thus, there is a slight angular overlap wherein both the E75 and E50 switches are closed and a similar slight overlap wherein the E50 and E25 switches are closed.

As indicated in FIG. 6, the ENDC cam operates four microswitches E20, E15, E10, and E5 which are spaced apart around its periphery at increments of 72. The switches E20, E15, E10, and E5 close and open in an overlapping sequence in a manner similar to the above described switches disposed about the periphery of the EQHC cam.

As indicated in FIG. 7 the EPC cam operates four microswitches E4, E3, E2, and E1 which are spaced apart around this periphery at increments of 72. The switches E4, E3, E2 and E1 close and open in an overlapping sequence in a manner similar to the above described switches disposed about the periphery of the EQHC cam. As an example of the manner in which the evaluator assembly registers the amount of change due a customer, consider a situation wherein a customer receives a $1.00 credit, but stops dispensing after receiving only 23 cents worth of gasoline. When the dispensing has stopped the shaft 51 will have rotated through 2.3 revolutions, the EPC and the ENDC cams will have rotated about 331, and the EQHC and ZPC cams will have rotated about 83. The angular positions of these cams provides an analog indication of change due. At these positions, the E and E2 switches will be closed whereas all the other switches disposed about the periphery of the EQHC, ENDC, and EPC cams will be open. The fact that the E75 switch is closed indicates that two coins of two different denominations are due (i.e., a half-dollar and a quarter). The fact that the E2 switch is closed indicates that two coins of the same denomination are due (i.e., two pennies). In combination, the switches indicate that 75 cents plus 2 cents (77 cents) change is due to the customer. Thus the ON or OFF state of the switches in the evaluator assembly simultaneously provide a digital indication of change due.

A PAY motor (PM) illustrated in FIG. 8 is a conventional synchronous motor powered by a V AC. The PM motor is located in the head box 55. Two cams PCI and PC2 are rotatably connected to the PM motor and operate a series of microswitches (see FIG. 2) disposed about their periphery. The PCl cam operates switches R1 through R5 and the PC2 cam operates switches R6 through R11. When the PM motor is energized to rotate the PCI and PC2 cams through one revolution, each of the switches closes momentarily and opens again with no angular overlap as in the switches in the evaluator assembly 200. The switches R1 through R11 are electrically connected with the switches disposed about the periphery of the cams in the evaluator unit in a manner shown in the schematic of FIG. 2 and described in detail hereinafter.

In FIG. 2 which comprises FIGS. 2A and 2B, the components which are located in the various boxes are shown in electrical schematic form within blocks having corresponding reference numerals. For example, the components within head box 55 are shown within block 55.

A conventional DC power supply 61 receives llOV AC power and has a +V output line and a 0V line. In the example described, power supply 61 produces 24V DC power so as to be compatible with commercially available relay components. Conduit indicated at 52 in FIG. 1 is provided for the wires interconnecting the head box 55 and the dispenser 20.

The head box 55 includes a credit display shown as block 62 which includes the numerical display light 57. The Allard Company sells a commercial credit display that includes the display light 57 and a diode matrix (not shown) which connects a 24V signal from any one of 10 input lines to any one of seven lines (not shown) so as to energize the display light 57 for displaying any selected one of 10 digits.

A conventional stepping switch 75 is provided to register credits entered into the dispensing unit 10. Stepping switch 75 includes a wiper arm 76 which is rotatable to make electrical connection with any one of a plurality of contacts. In the example described, the stepping switch has ten contacts individually connected to the credit display 62 and has its wiper arm 76 connected to the line. FIG. 2 shows the wiper arm in a zero position wherein the display light 57 in the credit display 62 displays the number zero. The stepping switch 75 also includes coils 78 and 79 which are individually energizable by the 1l0V AC line. Each time the coil 78 is energized, the wiper arm 76 rotates in one direction to break connection with one contact and to make connection with an adjacent contact on one side and the display light 57 then displays an incrementally larger number. Each time the coil 79 is energized, the wiper arm 76 rotates in the same manner but in the opposite direction and the display light 57 then displays an incrementally smaller number. Thus the coil 78 is energized to add credits and the coil 79 is energized to subtract credits.

A credit pulse generator 64 provides a 24V output pulse for each one dollar credit to be given a customer. A coil 70 of an ADR relay is connected to the credit pulse generator 64 and is momentarily energized by each 24V output pulse. The ADR relay has an arm 65 and a normally open contact 66 connected in series first portion of the dispensing of the gasoline corresponding to the last credit.

The SFV valve is turned on when the ZPR relay is en- I ergized by virtue of a closed circuit path which includes with the 110V AC line, the coil 78 and the 110V AC neutral line. Thus each time the ADR relay is momentarily energized, the coil 78 is energized and stepping switch 75 steps one position so as to register an incrementally larger number.

A cam 76' is mounted in a conventional manner for rotation with the wiper arm 76 of the stepping switch 75. A microswitch 85 operated by the cam 76' is open only while the wiper arm 76 is in zero position and is closed when the wiper arm 76 is not in zero position.

A coil 84 of 21 CSR relay is connected in series with the switch 85 and is energized by the +V line while the switch 85 is closed. Thus the CSR relay is not energized whenever the stepping switch 75 is in the zero position. For any given sales operation, the stepping switch 75 is in the zero position before any credits have been added in and also, as will be explained in more detail, during the dispensing of the gasoline corresponding to the last credit.

Before any gasoline is actually dispensed the reset lever 42 (FIG. 1) is rotated to reset the dispensing unit 10 to the zero position, and then the control handle 44 (FIG. 1) is rotated. Rotation of the control handle 44 causes the PCS switch in the switch box 47 to close. A pump control relay (PCR) has a coil 86 in series with the +V line, the switch PCS and the V line, and the PCR relay is energized while the PCS switch is closed. An arm 87 of the PCR relay is connected to receive 220V AC from one of the lines 25 and when the PCR relay is energized applies 220V AC to an associated normally open contact 88 which is connected back to the remote pump 24 by another one of the lines 25.

Consider now the circuitry associated with the operation of the assembly 26. The FFV valve is turned on when either of two circuit paths are closed. The first circuit path includes the 110V AC line, an arm 89 an associated normally open contact of the PCR relay and an arm 90 and an associated normally open contact of the CSR relay. This first circuit path is closed after at least one credit has been added in so as to energize the CSR relay and the control handle 44 has been rotated so as to actuate the PCS switch and energize the PCR relay. Owing to the deenergization of the CSR relay, this first circuit path opens again during the dispensing of the gasoline corresponding to the last credit. The second circuit path for energizing the FFV valve includes the 1 V AC line, an arm 91 and normally open contact 92 of a zero position relay (ZPR),.a normally open contact 93 and an arm 94 of a slow flow relay (SFR) which is connected to the FFV valve. This second circuit path provides a carry-over whereby the FFV valve is energized and as a result held open for the the 1 10V AC line, the arm 91 of the ZPR relay and its associated normally open contact 92 which is connected to the SFV valve.

A line 250 connects a coil 95 of the ZPR relay in a series circuit with the cam operated ZPS switch in the box 50 and the +V line. While the ZPS switch is closed, the ZPR relay is energized by the +V line. As pointed out above, the ZPS switch is open whenever the ZPC cam is between its zero position and its subtract position, and the angular distance between these two positions corresponds to approximately 3 cents worth of gasoline. Thus, in each sale, during the dispensing of the first 3 cents worth of gasoline, the ZPS switch is open and the ZPR relay is not energized. While the ZPR relay is unenergized, a circuit path is closed which includes the +V line, a resistor 96, a normally closed contact 97 and arm 98 of the ZPR relay, a capacitor 99, and a 0V line. A charge is stored by the capacitor 99 by virtue of this circuit path. After approximately 3 cents worth of gasoline is dispensed and the ZPC cam reaches its subtract position, the ZPS switch closes and energizes the ZPR relay. In response, the arm 98 and its associated normally open contact 100 of the ZPR relay make electrical connection. A coil 101 of a subtract relay (SUB) connected between the normally open contact 100 and 0V line is momentarily energized by the discharging of the capacitor 99.

An arm 102 and normally open contact 103 of the SUB relay make electrical connection while the SUB relay is momentarily energized and complete a circuit path from the 1 10V AC line to the neutral line through the coil 79 of the stepping switch 75. As pointed out above, energization of the coil 79 causes the stepping switch to rotate one position in a direction to subtract credits. If, for example, three $1.00 credits were added into the system, the three credits would be subtracted, one by one after dispensing $0.03, $1.03, $2.03 worth of gasoline, respectively. Thus, the wiper arm 76 is returned to its zero position where it remains for the last 97 cents worth of gasoline to be dispensed.

During the dispensing of the last 97 cents worth of gasoline, the first circuit path for energizing the FFV valve is open. However, for a carry-over portion the second circuit path therefor continues to energize the FFV valve. At the end of this carry-over portion, the cam operated slow flow switch SFS included in the box 50 is closed. The SFS switch is connected in series between the +V line and a line 251 which is connected to a coil 82 of the SFR relay. When the SFS switch closes, the SFR relay is energized and the FFV valve is turned off. On the other hand the SFV valve continues to be energized until the customer has received the last pennys worth of gasoline.

Eventually, when the customer has received all the gasoline he is entitled to, the return of the ZPC cam to its zero position results in the deenergization of the ZPR relay and consequently the deenergization of the SFV valve.

On the other hand, if the customer's gasoline tank should fill or if the customer should turn off the dispensing nozzle 36 before receiving the full amount of gasoline for which he has paid, the refund mechanism of the present invention comes into play. Briefly, the

refund operation proceeds as follows. The refund operation is commenced by rotating the control handle 44 back to its reset position so as to open the PCS switch. Circuitry responsive to the opening of the PCS switch energizes the PM motor so that it rotates through a number of revolutions, the number of revolutions depending on how much change is due the customer. During the first revolution of the PM motor the registration of the small change (i.e., less than $1.00) provided by the evaluator unit 200 is scanned by the actuation of the switches operated by the PM motoroperated cams and the coin return mechanisms pay out the small change. During each succeeding revolution of the PM motor, two half dollars are paid out until the customer has received his full change. Finally, the evaluator unit is reset to its zero position so as to be ready for the next sales operation.

When the control handle 44 is rotated back to its reset position, the PCS switch in the switch box 47 opens. The opening of the PCS switch removes the +V line from the coil 86 of the PCR relay. Consequently the PCR relay is deenergized and the 220V AC power is removed from the electrically operated pump 24. In addition, a coil 120 of a pay relay (PAY) is momentarily energized. The circuit for energizing the PAY relay is similar to that used for energizing the SUB relay. It includes a capacitor 121 which is charged through an arm 122 and normally open contact 123 of the PCR relay and a resistor 124 which is connected to the +V line. While the PCR relay is energized during the dispensing of gasoline the capacitor 121 is charged to +V. When the PCR relay is deenergized the arm 122 makes electrical connection with the normally closed contact 125 of the PCR relay and applies the stored voltage of the capacitor 121 to the coil 120 of the PAY relay. Once the PAY relay has been momentarily energized, it latches up for one rotation of the PM motor. For the purpose of latching up the PAY relay, a circuit path is provided from the coil 120 to the +V line through a normally open contact 126 and associated arm 127 of the PAY relay, a line 252, and the R11 switch. While the PAY relay is energized, the PAY motor receives 1 V AC power through an arm 132 to an associated normally open contact 133 of the PAY relay, and a line 253. After the PAY motor has rotated through somewhat less than one complete revolution, a cam operated switch R11 opens and removes the +V line from the coil 120 to unlatch the PAY relay.

The normally open contact 126 of the PAY relay is connected to a line 254 which connects the head box 55 to the evaluator unit 200. While the PAY relay is energized its arm 127 connects the +V line to the line 254 so as to enable the static read-out of the switches in the evaluator unit. The line 254 is connected to the normally open contact of each of the switches E1 through E4, to the arm of the switch E5, and the arm of the switch E25. Depending upon how much change is due the customer, one or more of the switches in the evaluator unit will be closed and will apply the voltage on the line 254 to one or more of the switches R1 through R10.

The arms of the switches E1 through E4 are individually connected to the normally open contacts of the R1 through R4 switches respectively. The arms of the R1 through R4 switches are connected together and are connected to a coil 150 of a PPR relay. The normally open contact of the switch E1 is connected to the arm of the switch E2, the normally closed contact of the switch E2 is connected to the arm of the switch E3, and the normally closed contact of the switch E3 is connected to the arm of the switch E4.

The PPR relay has a normally open contact 151 connected to the 1 10V AC line and an arm 152 connected to a conventional electrically operated penny pay mechanism (PPM). Each time the PPR relay is energized the PPM is energized and a penny is paid out from the coin storage (not shown).

When the E1 switch is closed, and the E2 through E4 switches are open, a single penny is due the customer. With the switch E1 closed, the voltage on the line 254 is applied to the normally open contact of the switch R1. With the switches E2 through E4 open, the voltage on the line 254 is not applied to the switches R2 through R4. Thus as the PCI cam momentarily closes its associated switches, only the switch R1 is operative to energize the PPR relay. Thus a single penny is paid out to the customer.

With the switch E2 closed, the voltage on the line 254 is applied to the normally open contacts of the switches R1 and R2. This is true whether the E1 switch is open or is closed as it would be for the small angular overlap described above. When only the switch E2 is closed, the line 254 is connected to the normally open contact of the switch R2 through the closed switch E2 and is connected to the normally open contact of the switch R1 through the closed switch E2 and the open switch E1. With the switches E3 and E4 open, the voltage on the line 254 is not applied to the normally open contacts of the switches R3 and R4. Thus as the PC1 cam momentarily closes its associated switches, only the switches R1 and R2 are operative to energize the PPR relay. Thus two pennies are paid out in sequence to the customer.

Similarly, with the switch E3 closed, the circuit paths are such that three pennies are paid out in sequence from the coin storage, and with the switch E4 closed, the circuit paths are such that four pennies are paid out in sequence from the coin storage.

An NPR relay is provided energizing a conventional nickel pay mechanism (NPM). To this end, the NPR relay has switch contacts 513 connected between the V AC line and the NPM. The NPR relay has a coil 154 which is energized under the control of the R5 switch and the switches disposed around the periphery of the ENDC cam. When a nickel is to be paid a customer, either the switch E5 is closed (i.e., when $0.05, or $0.30 is due) or the switch E15 is closed (i.e., when $0.15, or $0.40). With the switch E5 closed, the voltage on the line 254 is applied to the arm of the switch R5. With the switch E15 closed, the voltage on the line 254 is applied to the arm of the switch R5 through the switch E15 and a diode 155. In either case, as the PCI cam momentarily closes its associated switches, the switch R5 is operative to energize the NPR relay and a nickel is paid out to the customer.

A DPR relay is provided for energizing a conven tional dime pay mechanism (DPM). To this end, the DPR has switch contacts 156 connected between the 1 10V AC line and the DPM. The DPR relay has a coil 157 which is energized under the control of the switches R6 and R7 and the switches disposed around the periphery of the ENDC cam. When a single dime is to be paid to the customer, either the switch E10 is closed (e.g., $0.10, or $0.35) or the switch E15 is closed (e.g., $0.15). When two dimes are to be paid to the customer, the switch E20 is closed (e.g., $0.20). With the switch E closed, the voltage on the line 254 is applied to the arm of the switch R6. The normally open contact of the switch R6 is connected to the coil 157 of the DPR relay. With the switch E closed the voltage on the line 254 is applied to the arm of the switch R6 through a diode 158. In either case, as the PC2 cam momentarily closes its associated switches, the switch R6 is operative to energize the DPR relay. Thus a single dime is paid out to the customer. v

The normally open contact of the switch E is connected to the arm of the switch R7. The normally closed contact of the switch R7 is connected to the arm of the switch R6. The normally open contact of the switch R7 is connected to the coil 157 of the DPR relay. With the switch E20 closed, the voltage on the line 254 is applied to the arm of the switch R6 through the closed switch E20 and the open switch R7. Thus when R6 is closed under the action of PC2 cam, the DPR relay is energized to pay out one dime. In addition, the voltage on the line 254 is switched through the switch R7 when it momentarily closes and in response a second dime is paid out.

A QPR relay is provided for energizing a conventional quarter pay mechanism (QPM). To this end, the QPR relay has switch contacts 159 connected between the llOV AC line and the QPM. The QPR relay has a coil 160 which is energized under the control of the switch R8 and the switches disposed about the periphery of the EQHC cam.

When a quarter is to be returned to the customer, either the E switch is closed or the E75 switch is closed. With the E25 switch closed, the voltage on the line 254 is applied to the arm of the R8 switch. With the E75 switch closed, the voltage on the line 254 is switched through the closed E75 switch and a diode 161 to the arm of the R8 switch. The normally open contact of the R8 switch is connected to the coil 160 of the QPR relay. Thus as the PC2 cam momentarily closes its associated switches, the R8 switch is operative to energize the QPR relay, and a quarter is paid out to the customer by the energized QPM.

An HPR relay is provided for energizing a conventional half-dollar pay mechanism (HPM). The HPR relay has switch contacts 162 connected between the 110V AC line and the I-IPM. The HPR relay has a coil 163 which is energized under the control of the switches R9 and R10 and the switches disposed about the periphery of EQl-IC cam. During the payout of the small change, at most a single half-dollar will be paid out by the HPM. When a half-dollar is to be paid to the customer, either the E50 switch or the E75 switch is closed. With the E50 switch closed, the voltage on the line 254 is applied to the arm of the switch R9. The normally open contact of the switch arm R9 is connected to the coil 163 of the HPR relay. With the E75 switch closed, the voltage on the line 254 is applied to the arm of the R9 switch through a diode 164. Thus as the PC2 cam momentarily closes its associated switches, the switch R9 is operative to energize the HPR relay and a half-dollar is paid to the customer by the I-IPM.

After the small change due the customer has been paid out, the PAY relay is deenergized by virtue of the opening of the R11 switch. It should be noted that the R11 switch will open only momentarily under the action of the PC2 cam and then close again. This is because of the inertia of the PM motor keeps its rotor moving through a small arc after the power is removed from the motor. Thus the PC2 cam opens the R11 switch while the PM motor is being powered and then closes it again while the PM motor coasts to a stop.

Consider now briefly the pay out of one dollar increments. For each unused one dollar credit, the customer is paid two half-dollars. After the payout of each one dollar increment the stepping switch is actuated to subtract one credit. When the stepping switch reaches its zero position the cam operated switch opens and deenergizes the CSR relay. When the CSR relay is deenergized the circuitryfor paying out the one dollar increments is disabled.

A PAB relay is provided for controlling the energization of the PM motor for its revolutions relating to the payout of one dollar increments. The circuit for energizing the PAB relay is similar to that used for energizing the PAY relay. It includes a capacitor 134 which is charged through a resistor 135 while the PAY relay is energized and is discharged through a coil 136 of the PAB relay upon the deenergization of the PAY relay. Once the PAB relay has been momentarily energized, it latches up for one or more rotations of the PM motor. An arm 144 and normally open contact 145 of the PAB relay switch the 110V AC line to the PM motor while the PAB relay is latched.

Two circuit paths are involved in latching the PAB relay. In the first circuit path, the +V line is switched to the coil 136 by an arm 137 and normally open contact 138 of the PAB relay and an arm 139 and normally open contact 140 of the CSR relay and a diode 141. This first circuit path keeps the PAB relay latched up until the CSR relay is deenergized under the action of the switch 85. In the second circuit path, the +V line is switched by the switch R11 and an arm 142 and normally open contact 143 of the PAB relay to the coil 136. This second circuit path keeps the PAB relay latched up after the CSR relay has been deenergized and until the R11 switch opens under the action of the PC2 cam.

The PAB relay has an arm 144 connected to the AC line, a normally open contact 145 connected to the line 253, and it switches V AC power to the PM motor via the line 253. The junction of the contact of the CSR relay and the anode of the diode 141 is connected via a line 256 to the arm of the switch R10. Thus the voltage on the +V line is connected to the line 256 when the PAB and CSR relays are energized. The normally open contact of the switch R11 is connected via a line 257 to the anode end of a diode 146 which has its cathode end connected to the coil 101 of the SUB relay. Thus each time the R10 switch is closed under the action of cam PC2 while the voltage of the +V line is applied to the line 256, the SUB relay is energized and consequently stepping switch 75 is decremented by one position. Eventually the stepping switch 75 returns to its zero position and the cam 76 opens the switch 85. In response the CSR relay is deenergized and the first circuit involved in latching up the PAB relay opens. In addition the line 256 will no longer connect the +V line to the switch R10. This is true because of the blocking action of the now reverse-biased diode 141 even though the PAB relay remains latched. Since the switch R10 now no longer receives the voltage from the +V line there is no further payout of half-dollars. After all the change due the customer is returned, the

EZM drives the shaft 48 until the evaluator assembly is nulled. The energization and deenergization of the EZM is controlled by a series of relay contacts shown generally as block 301 for simplicity of the drawing. The EZM is energized by block 301 when the PCR, PAB, and CSR relays are deenergized and the ZPR relay is energized. When the evaluator assembly 200 reaches its null, the ZPR relay is deenergized and the EZM is deenergized.

It should be noted that an additional circuit path is provided for causing the subtraction of a credit from the stepping switch 75 which has not been previously discussed. The purpose of this circuit path is to prevent the payout of more change than is due the customer. To understand the need for this circuit, recall that about 3 cents worth of gasoline in excess of an even dollar must be dispensed before the ZPC cam reaches its subtract position. Thus after the customer has received $0.03, $1.03, etc., the stepping switch 75 is decremented step-by-step.

If the customer has paid for $3.00 worth of gasoline and his gasoline tank should fill at say $2.02, then ZPC cam will have passed the subtract position twice and be in a position between the zero position and the subtract position. In this region the ZPS switch is open and the ZPR relay is not energized. Since the ZPC cam did not pass through its zero position three times the stepping switch 75 will inaccurately indicate that he is due 1 .00. The change due of course is $0.98 and that is accurately indicated by the evaluator assembly 200.

To prevent the payout of this extra dollar, a diode 300 is connected between the arms of the switches Rl through R4 to the ZPR relay by a line 254. Thus when the pennies are returned to the customer when the switches R1 through R4 close, the diode 254 couples a voltage to the ZPR relay so as to energize it. In response the circuitry coupling the ZPR relay to the stepping switch 75 is operated to subtract the extra credit.

I claim:

1. A change calculating coin-return system comprisa coin storage for storing coins of various denominations;

a plurality of coin payout mechanisms, each associated with a different denomination and each energizable to payout a coin of its associated denomination from the coin storage;

means for registering numbers;

means for storing a preset number in the registering means;

a rotatable shaft;

means operable to rotate the rotatable shaft and operable to stop rotating the shaft before the shaft has been rotated through a number of angular degrees which is proportional to the preset number;

an evaluator assembly comprising first means coupled to the rotatable shaft for rotation when the shaft is rotated and remaining stationary while the rotatable shaft is stopped for providing an analog indication of change to be returned as a function of the angular position of the stationary first means, and a plurality of switching circuits selectively closed by the first means for simultaneously providing a digital indication corresponding to the analog indication; and

means for energizing the coin payout mechanisms in accordance with digital indication provided by the switching circuits while the rotatable shaft and evaluator assembly first means are stationary.

2. A system according to claim 1 wherein at least one of the switching circuits provides an indication that a specified plurality of coins of a first denomination are to be returned, and the means for energizing the coin payout mechanisms includes means for energizing the coin payout mechanism associated with the first denomination a number of times equal to the specified plurality.

3. A system according to claim 1 wherein a first one of the switching circuit provides an indication that a coin of a first denomination and that a coin of a second denomination are to be returned, and the means for energizing the coin payout mechanisms includes means responsive to the first switching circuit for energizing the coin payout mechanism associated with the first denomination and means responsive to the first switching circuit for energizing the coin payout mechanism associated with the second denomination.

4. A system according to claim 1, the means for energizing the coin payout mechanisms being operable to scan the digital indication and operate the coin payout mehanisms while scanning and including a motor, cam means rotatably driven by the motor, and a plurality of switches operated sequentially in response to rotation of the motor and electrically coupled between the switching circuits in the evaluator assembly and the coin payout mechanisms.

5. A change calculating coin-return system comprising;

a coin storage for storing coins of various denominations;

a plurality of coin payout mechanisms, each associated with a different denomination and each energizable to payout a coin of its associated denomination from the coin storage;

means for registering numbers;

means for storing a preset number in the registering means;

a rotatable shaft;

means operable to rotate the rotatable shaft and operable to stop rotating the shaft before the shaft has been rotated through a number of angular degrees which is proportional to the preset number;

an evaluator assembly comprising cam means rotatably coupled to the rotatable shaft and stationary while the rotatable shaft is stopped for providing an analog indication of change to be returned, and a plurality of switches operated by the cam means for simultaneously providing a digital indication corresponding to the analog indication; and

means for energizing the coin payout mechanisms in accordance with the digital indication provided by the switches;

said evaluator assembly including an individual cam providing an analog indication of change to be returned of a single denomination and predetermined number of switches each disposed around the periphery of the individual cam and each for indicating a different total number of coins to be returned, the predetermined number corresponding to the maximum total number of coins of the single denomination to be returned as change; and

said means for energizing the coin payout mechanisms including means for scanning the switches and for energizing the coin payout mechanism associated with the single denomination a number of times equal to the total number indicated.

6. A system according to claim 5 wherein the evaluator assembly includes a second individual cam providing an analog indication of change to be returned of a first and of a second denomination, and a plurality of switches operated by the second individual cam, a first switch of the plurality indicating simultaneously that coins of the first and the second denomination are to be returned; and wherein the means for energizing the coin payout mechanisms includes means responsive to the first switch for energizing the coin payout mechanism associated with the first denomination and means responsive to the first switch for energizing the coin payout mechanism associated with the second denomination.

7. in a coin-return system for a fluid-dispensing unit which includes means computing the value of fluid dispensed from the unit, the apparatus comprising:

a coin storage for storing coins of various denominations;

a plurality of coin payout mechanisms each associated with a different denomination and each energizable to return coins of its associated denomination from the coin storage;

an evaluator assembly comprising first means rotated by the computing means until the dispensing of fluid from the unit stops, the first means providing while stationary an analog indication of change to be returned, and a plurality of switching circuits operated by the first means for simultaneously providing a digital indication corresponding to the analog indication; and

means operable while the first means are stationary for energizing the coin payout mechanisms in accordance with the digital indication provided by the switching circuits.

8. Apparatus according to claim 7 wherein the means for energizing the payout mechanisms includes a motor, cam means rotatably driven by the motor, and a plurality of switches operated sequentially in response to rotation of the motor and electrically coupled between the switching circuits in an evaluator assembly and the coin payout mechanisms. 

1. A change calculating coin-return system comprising: a coin storage for storing coins of various denominations; a plurality of coin payout mechanisms, each associated with a different denomination and each energizable to payout a coin of its associated denomination from the coin storage; means for registering numbers; means for storing a preset number in the registering means; a rotatable shaft; means operable to rotate the rotatable shaft and operable to stop rotating the shaft before the shaft has been rotated through a number of angular degrees which is proportional to the preset number; an evaluator assembly comprising first means coupled to the rotatable shaft for rotation when the shaft is rotated and remaining stationary while the rotatable shaft is stopped for providing an analog indication of change to be returned as a function of the angular position of the stationary first means, and a plurality of switching circuits selectively closed by the first means for simultaneously providing a digital indication corresponding to the analog indication; and means for energizing the coin payout mechanisms in accordance with digital indication provided by the switching circuits while the rotatable shaft and evaluator assembly first means are stationary.
 2. A system according to claim 1 wherein at least one of the switching circuits provides an indication that a specified plurality of coins of a first denomination are to be returned, and the means for energizing the coin payout mechanisms includes means for energizing the coin payout mechanism associated with the first denomination a number of times equal to the specified plurality.
 3. A system according to claim 1 wherein a first one of the switching circuit provides an indication that a coin of a first denomination and that a coin of a second denomination are to be returned, and the mEans for energizing the coin payout mechanisms includes means responsive to the first switching circuit for energizing the coin payout mechanism associated with the first denomination and means responsive to the first switching circuit for energizing the coin payout mechanism associated with the second denomination.
 4. A system according to claim 1, the means for energizing the coin payout mechanisms being operable to scan the digital indication and operate the coin payout mechanisms while scanning and including a motor, cam means rotatably driven by the motor, and a plurality of switches operated sequentially in response to rotation of the motor and electrically coupled between the switching circuits in the evaluator assembly and the coin payout mechanisms.
 5. A change calculating coin-return system comprising; a coin storage for storing coins of various denominations; a plurality of coin payout mechanisms, each associated with a different denomination and each energizable to payout a coin of its associated denomination from the coin storage; means for registering numbers; means for storing a preset number in the registering means; a rotatable shaft; means operable to rotate the rotatable shaft and operable to stop rotating the shaft before the shaft has been rotated through a number of angular degrees which is proportional to the preset number; an evaluator assembly comprising cam means rotatably coupled to the rotatable shaft and stationary while the rotatable shaft is stopped for providing an analog indication of change to be returned, and a plurality of switches operated by the cam means for simultaneously providing a digital indication corresponding to the analog indication; and means for energizing the coin payout mechanisms in accordance with the digital indication provided by the switches; said evaluator assembly including an individual cam providing an analog indication of change to be returned of a single denomination and predetermined number of switches each disposed around the periphery of the individual cam and each for indicating a different total number of coins to be returned, the predetermined number corresponding to the maximum total number of coins of the single denomination to be returned as change; and said means for energizing the coin payout mechanisms including means for scanning the switches and for energizing the coin payout mechanism associated with the single denomination a number of times equal to the total number indicated.
 6. A system according to claim 5 wherein the evaluator assembly includes a second individual cam providing an analog indication of change to be returned of a first and of a second denomination, and a plurality of switches operated by the second individual cam, a first switch of the plurality indicating simultaneously that coins of the first and the second denomination are to be returned; and wherein the means for energizing the coin payout mechanisms includes means responsive to the first switch for energizing the coin payout mechanism associated with the first denomination and means responsive to the first switch for energizing the coin payout mechanism associated with the second denomination.
 7. In a coin-return system for a fluid-dispensing unit which includes means computing the value of fluid dispensed from the unit, the apparatus comprising: a coin storage for storing coins of various denominations; a plurality of coin payout mechanisms each associated with a different denomination and each energizable to return coins of its associated denomination from the coin storage; an evaluator assembly comprising first means rotated by the computing means until the dispensing of fluid from the unit stops, the first means providing while stationary an analog indication of change to be returned, and a plurality of switching circuits operated by the first means for simultaneously providing a digital indication corresponding to the analog indication; and meaNs operable while the first means are stationary for energizing the coin payout mechanisms in accordance with the digital indication provided by the switching circuits.
 8. Apparatus according to claim 7 wherein the means for energizing the payout mechanisms includes a motor, cam means rotatably driven by the motor, and a plurality of switches operated sequentially in response to rotation of the motor and electrically coupled between the switching circuits in an evaluator assembly and the coin payout mechanisms. 